DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Specification
The title of the invention is not descriptive. A new title is required that is clearly indicative of the invention to which the claims are directed.
The following title is suggested: SUBSTRATE PROCESSING METHOD AND SUBSTRATE PROCESSING APPARATUS FOR FORMING A FORMING A METAL LAYER IN A RECESS PORTION OF AN INSULATOR, AND FOR REMOVING METAL FROM SIDEWALLS OF THE RECESS IN WHICH A METAL SILICIDE IS FORMED
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1, 3-9, and 11-14 are rejected under 35 U.S.C. 103 as being unpatentable over Fu; Xinyu et al. (US 2016/0276214; hereinafter Fu) in view of Yamasaki; Hideaki et al. (US 2018/0308709; hereinafter Yamasaki).
Regarding claim 1, Fu discloses a substrate processing method, comprising:
by supplying a substrate (200; Figs 2A-2C; ¶ [0017]) in which an insulator layer (dielectric layer 212; Figs 2A-2C; ¶ [0017]) is deposited on a silicon layer (204; Figs 2A-2C; ¶ [0017]; 200 may comprise silicon and silicon oxide, the dielectric 212 being the silicon oxide, therefor 204 being the silicon) and a recess portion (feature 202; Figs 2A-2C; ¶ [0018]) is formed in the insulator layer, forming a metal layer (208, which may be titanium; Figs 2B-2C; ¶ [0020,0031]) of a first metal (titanium (Ti)) on a surface of the silicon layer exposed in the recess portion; and
subsequently, by supplying a second metal halide gas (tungsten pentachloride (WCI5); ¶ [0022]) which includes a second metal (tungsten (W)) which reacts with the first metal, to the substrate in which the silicon of the silicon layer is diffused to the metal layer to form a metal silicide layer (titanium silicide; ¶ [0031]), removing the first metal adhering to a side wall surface of the recess portion (a portion of the titanium first metal is removed from the sidewall of 202; Fig 2C, as compared to Fig 2B; ¶ [0031]).
Fu discloses that the metal layer 208 may be deposited using any suitable deposition process (¶ [0020]), but does not disclose the forming is by supplying a first metal halide gas including the first metal to the substrate, and the second metal of the second metal halide gas is different from the first metal.
In the same field of endeavor, Yamasaki discloses a method of forming a metal layer (titanium film; ¶ [0053]) of a first metal (titanium; ¶ [0053]) by supplying a first metal halide gas (titanium tetrachloride (WCI4); ¶ [0053]) including the first metal to a substrate (workpiece W, similar to that of Fu; Fig 2; ¶ [0022]). Accordingly, it would have been obvious to a person having ordinary skill in the art to have formed the metal layer 208 of Fu by a similar method as Yamasaki. One would have been motivated to do this, with a reasonable expectation of success, because Yamasaki discloses that the metal layer 208 may be formed by any suitable deposition process, and does not supply a detailed method of any deposition process, while Yamasaki discloses the detailed deposition method for the same titanium material on the similar substrate having similar structure and materials.
In addition, in an alternate viewpoint, one may consider that the method of Yamasaki, wherein a titanium layer R1 (Yamasaki; Fig 6; ¶ [0053]) is removed from a side wall of a recess after formation of titanium silicide in region R2 at the bottom of the recess (Yamasaki; Fig ; ¶ [0054]), may alternatively use for the removal of the titanium layer R1 the removal method of Fu, since Fu discloses that the method may be advantageously used to etch any unreacted titanium without etching a titanium silicide layer; Fu; ¶ [0031]).
Regarding claim 3, Fu in view of Yamasaki discloses the substrate processing method of Claim 1, wherein the first metal is titanium, and metal silicide of the metal silicide layer is titanium silicide (as applied to Claim 1; Fu; ¶ [0031])).
Regarding claim 4, Fu in view of Yamasaki discloses the substrate processing method of Claim 3, wherein the first metal halide gas is a TiCl4 gas (as applied to Claim 1; Yamasaki; ¶ [0053]).
Regarding claim 5, Fu in view of Yamasaki discloses the substrate processing method of Claim 3, wherein the second metal halide gas is a WCl5 gas (as applied to Claim 1; Fu; ¶ [0022]).
Regarding claim 6, Fu in view of Yamasaki discloses the substrate processing method of Claim 1, further comprising, after the removing the first metal, forming a conductor on the substrate and embedding the conductor in the recess portion. (As applied to claim 1, after removing the portion of the titanium first metal, the feature 202 may be filled with a conductive fill material; Fu; ¶ [0030].)
Regarding claim 7, Fu discloses substrate processing apparatus (a cluster tool; Fig 3; ¶ [0033-42]), comprising:
a first processing module including:
a processing container (302; Fig 3; ¶ [0034-35]) having a stage (308; Fig 3; ¶ [0035]) on which a substrate (200; Figs 2A-2C; ¶ [0017]; corresponding to 310 of Fig 3 {¶ [0035]}) is placed;
and a first gas supplier (319; Fig 3; ¶ [0038]);
a second processing module (Fu discloses the apparatus may be part of a cluster tool {¶ [0033]}, which known in the art to comprise multiple processing modules; see Fig 3 and associated description of Yamazaki for one example of a cluster tool) including: a processing container (302; Fig 3; ¶ [0034-35]) having a stage (308; Fig 3; ¶ [0035]) on which the substrate is placed (310; Fig 3; ¶ [0033-42]); and
a second gas supplier (another of 319 or similar, where one or more valves may provide one or more process gases; Fig 3; ¶ [0038]) configured to supply a second metal halide gas (tungsten pentachloride (WCI5); ¶ [0022]) including a second metal (tungsten (W)) different from a first metal (titanium (Ti)) and reacting with the first metal of a metal layer (208, which may be titanium; Figs 2B-2C; ¶ [0020,0031]) on the substrate to the processing container; and
a controller (350; Fig 3; ¶ [0034,0042-43]),
wherein the controller is configured to output a control signal (¶ [0043]).
Fu discloses that the metal layer 208 may be deposited using any suitable deposition process (¶ [0020]), but does not disclose the first gas supplier is configured to supply a first metal halide gas including a first metal to the processing container; and, a processing sequence for the control signal to execute.
In the same field of endeavor, Yamasaki discloses a method of forming a metal layer (titanium film; ¶ [0053]) of a first metal (titanium; ¶ [0053]) by supplying a first metal halide gas (titanium tetrachloride (WCI4); ¶ [0053]) including the first metal to a substrate (workpiece W, similar to that of Fu; Fig 2; ¶ [0022]). Accordingly, it would have been obvious to a person having ordinary skill in the art to have configured the first gas supplier of Fu to supply a first metal halide gas including the first metal, in order to complete a configuration of the substrate processing apparatus capable to form the metal layer 208 of Fu by a similar method as Yamasaki, and thereby complete the method of Fu, including the depositing the metal layer 208. One would have been motivated to do this, with a reasonable expectation of success, for the following reasons: (1) Yamasaki discloses that the metal layer 208 may be formed by any suitable deposition process, and does not supply a detailed method of any deposition process, while Yamasaki discloses the detailed deposition method for the same titanium material on the similar substrate having similar structure and materials. (2) each of Fu and Yamasaki (Yamasaki; Fig 3; ¶ [0023-50]) disclose a similar cluster tool apparatus with similar configurable capabilities to adapt to a variety of processing requirements, and such cluster tools and their configurations are well-known in the art.
In addition, in an alternate viewpoint, one may consider that the method and apparatus of Yamasaki, wherein a titanium layer R1 (Yamasaki; Fig 6; ¶ [0053]) is removed from a side wall of a recess after formation of titanium silicide in region R2 at the bottom of the recess (Yamasaki; Fig ; ¶ [0054]), may alternatively use for the removal of the titanium layer R1 the removal method of Fu, since Fu discloses that the method may be advantageously used to etch any unreacted titanium without etching a titanium silicide layer; Fu; ¶ [0031]). Since the cluster tool apparatus of Yamasaki is similar to that of Fu, the apparatus of Yamasaki may be configured similarly to complete such a method.
In view of the above explanation, it would be obvious to a person having ordinary skill in the art, that the controller may be configured to execute the processing sequence comprising steps for completing a method of Fu in view of Yamasaki (or a method of Yamasaki in view of Fu, in an alternate viewpoint), wherein the controller is configured to output a control signal for executing:
forming a metal layer (Fu; 208, which may be titanium; Figs 2B-2C; ¶ [0020,0031]) of the first metal (Ti) included in the first metal halide gas (Yamasaki; WCI4) on a surface of a silicon layer (Fu; 204; Figs 2A-2C; ¶ [0017]) exposed in a recess portion (Fu; feature 202; Figs 2A-2C; ¶ [0018]) by placing, on the stage of the first processing module, the substrate in which an insulator layer (Fu; dielectric layer 212; Figs 2A-2C; ¶ [0017]) is deposited on the silicon layer and the recess portion is formed in the insulator layer and supplying the first metal halide gas to the processing container of the first processing module from the first gas supplier; and subsequently, removing the first metal adhering to a side wall surface of the recess portion (Fu; a portion of the titanium first metal is removed from the sidewall of 202; Fig 2C, as compared to Fig 2B; ¶ [0031]) by placing, on the stage of the second processing module, the substrate in which the silicon of the silicon layer is diffused to the metal layer to form a metal silicide layer (Fu; titanium silicide; ¶ [0031]) and supplying the second metal halide gas (Fu; WCI5) to the processing container of the second processing module from the second gas supplier.
Regarding claim 8, Fu in view of Yamasaki discloses the substrate processing apparatus of Claim 1, but does not disclose wherein the first processing module and the second processing module share the stage and the processing container. However, this would have been obvious to a person having ordinary skill in the art for the following reasons (1) given the processing sequence of claim 7, the process steps of the first processing module and the second process module are compatible with one another in terms of defectivity and module parameter requirements and (2) it would likely improve manufacturing throughput and simplicity, and cost of the apparatus for the modules to share the stage and processing container. It is further noted that Yamasaki discloses an etching apparatus 10B (Fig 5) that has the same configuration as a film forming apparatus 10A (Fig 4); that is, they may share a stage and controller
Regarding claim 9, Fu in view of Yamasaki discloses the substrate processing apparatus of Claim 7, but does not specifically disclose the limitation of claim 9. However, Yamasaki discloses
a vacuum transfer chamber (TC; Fig 3; ¶ [0027]) to which a processing container (process module chamber; ¶ [0028]) of a first processing module (PM1; Fig 3; ¶ [0023]) and a processing container of a second processing module (any of PM1-PM4; Fig 3; ¶ [0023]) are connected; and
a substrate transfer mechanism (TU2; Fig 3; ¶ [0027]) disposed within the vacuum transfer chamber.
It would have been obvious to a person having ordinary skill in the art to have configured substrate processing apparatus of Claim 1 in this manner, wherein the controller is further configured to output a control signal for executing:
after the forming the metal layer of the first metal, transferring the substrate to the stage of the second processing module from the stage of the first processing module via the vacuum transfer chamber by the substrate transfer mechanism; and subsequently, removing the first metal. One would have been motivated to do this, with a reasonable expectation of success, because this is a well-known and configuration and method in the art, and as applied to Claim 1, the substrate processing apparatus (Fu; Fig 3) is a similar cluster tool as Yamasaki.
Regarding claim 11, Fu in view of Yamasaki discloses the substrate processing method of Claim 7, wherein the first metal is titanium, and metal silicide of the metal silicide layer is titanium silicide (as applied to Claim 7; Fu; ¶ [0031])).
Regarding claim 12, Fu in view of Yamasaki discloses the substrate processing apparatus of Claim 11, wherein the first metal halide gas is a TiCl4 gas (as applied to Claim 7; Yamasaki; ¶ [0053]).
Regarding claim 13, Fu in view of Yamasaki discloses the substrate processing apparatus of Claim 11, wherein the second metal halide gas is a WCl5 gas (as applied to Claim 7; Fu; ¶ [0022]).
Regarding claim 14, Fu in view of Yamasaki discloses the substrate processing apparatus of Claim 7, but does not disclose further comprising the limitations of Claim 14. However, Yamasaki discloses a substrate processing apparatus that may comprise a fourth processing module (Yamasaki; PM1-PM4; Fig 3; ¶ [0023]), and Fu discloses the substrate processing apparatus of Claim 1 may be a cluster tool. In addition, Fu discloses the method including, after the removing the first metal, performing film formation of a conductor on the substrate and embedding the conductor in the recess portion. (Fu; after removing the portion of the titanium first metal, the feature 202 may be filled with a conductive fill material; ¶ [0030]).
Accordingly, it would have been obvious to have configured the substrate processing apparatus of Claim 7 to have a similar fourth processing module including: a processing container having a stage on which the substrate is placed; and a fourth gas supplier configured to supply a raw material gas of the conductor (conductive fill material of Fu) to the processing container, wherein the controller is further configured to output a control signal for executing: after the removing the first metal, performing film formation of the conductor on the substrate by placing the substrate on the stage of the fourth processing module and supplying the raw material gas to the processing container from the fourth gas supplier; and embedding the conductor in the recess portion. One would have been motivated to do this in order to complete the method of Fu in view of Yamasaki, and would have had a reasonable expectation of success because each of the limitations is contained within the two references and their combination to arrive at Claim 14 is well-within the skill of a person of ordinary skill in the art.
Claims 2, 6 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Fu; Xinyu et al. (US 2016/0276214; hereinafter Fu) in view of Yamasaki; Hideaki et al. (US 2018/0308709; hereinafter Yamasaki) and further in view of Cheng; Chung-Liang et al. (US 2020/0098623; hereinafter Cheng).
Regarding claim 2, Fu in view of Yamasaki discloses the substrate processing method of Claim 1, but does not disclose further comprising, after the forming the metal layer, oxidizing the first metal adhering to the side wall surface by heating the substrate in an atmosphere in which an oxidizing gas is supplied, wherein in the removing the first metal, the first metal oxidized in the oxidizing the first metal is removed.
In the same field of endeavor, Cheng discloses a method of forming a similar substrate feature comprising, after the forming a metal layer (544; Fig 5D; ¶ [0047-49]), oxidizing a first metal (titanium) adhering to a side wall surface (534,536; Fig 5D; ¶ [0046]) by heating a substrate in an atmosphere in which an oxidizing gas (oxygen; ¶ [0050]) is supplied, and
removing the first metal (with, for example, WCl5; Fig 5G; ¶ [0053]) wherein the first metal oxidized (546; Fig 5E; ¶ [0050]) in the oxidizing the first metal is removed.
Accordingly, it would have been obvious to a person having ordinary skill in the art to have combined the method of Cheng for selectively removing the first metal adhering to a sidewall surface, with the method of claim 1. One would have been motivated to do this to ensure that only the oxidized portions of the metal layer, and not the bottom portion (Cheng; ¶ [0053]), are removed. One would have had a reasonable expectation of success because of the similar endeavors of Cheng, Fu, and Yamazaki, comprising similar substrate features, similar metals, and similar metal halide removal gases.
Regarding claim 6, in the alternate viewpoint considered under Claim 1, wherein in the method of Yamasaki, wherein a titanium layer R1 (Yamasaki; Fig 6; ¶ [0053]) is removed from a side wall of a recess after formation of titanium silicide in region R2 at the bottom of the recess (Yamasaki; Fig ; ¶ [0054]), Yamasaki does not disclose after the removing the first metal, forming a conductor on the substrate and embedding the conductor in the recess portion.
However, in the same field of endeavor Cheng discloses a method of forming a similar substrate feature comprising, after removing a first metal (544; Fig 5D-5G; ¶ [0047-54]), forming a conductor (550; Fig 5I; ¶ [0056]) on a substrate and embedding the conductor in a recess portion (540; Fig 5G; ¶ [0046]). Accordingly, it would have been obvious to have combined the forming and embedding a conductor of Cheng with the alternate viewpoint method of Claim 1. One would have had a reasonable expectation of success because of the similar substrate features and materials of Cheng, Yamasaki, and Fu, and because this method is well known in the art.
Regarding claim 10, Fu in view of Yamasaki discloses the substrate processing apparatus of Claim 7, but does not disclose the further limitations of claim 10. However, Fu discloses a third processing module including:
a processing container (302; Fig 3; ¶ [0034-35]) having a stage (308; Fig 3; ¶ [0035]) on which a substrate (200; Figs 2A-2C; ¶ [0017]; corresponding to 310 of Fig 3 {¶ [0035]}) is placed; and
a third gas supplier (another of 319 or similar, where one or more valves may provide one or more process gases; Fig 3; ¶ [0038]); wherein, the a third processing module may be part of a cluster tool (Fu; according to claim 7); and
Yamasaki discloses a cluster tool having a third processing container (Yamazaki; one of PM1-PM4; Fig 3; ¶ [0023]).
In the same field of endeavor, Cheng discloses a method of forming a similar substrate feature comprising, after the forming a metal layer (544; Fig 5D; ¶ [0047-49]), oxidizing a first metal (titanium) adhering to a side wall surface (534,536; Fig 5D; ¶ [0046]) by heating a substrate in an atmosphere in which an oxidizing gas (oxygen; ¶ [0050]) is supplied, and
removing the first metal (with, for example, WCl5; Fig 5G; ¶ [0053]) wherein the first metal oxidized (546; Fig 5E; ¶ [0050]) in the oxidizing the first metal is removed.
Accordingly, it would have been obvious to a person having ordinary skill in the art to have combined the method of Cheng for selectively removing the first metal adhering to a sidewall surface, with the method of claim Fu in view of Yamasaki, and to have configured the substrate processing apparatus in which to execute the method, wherein the controller is further configured to output a control signal for executing:
after the forming the metal layer, oxidizing the first metal adhering to a side wall surface by placing the substrate on the stage of the third processing module and heating the substrate in an atmosphere in which the oxidizing gas is supplied from the third gas supplier; and
in the removing the first metal, removing the first metal oxidized in the oxidizing the first metal is removed.
One would have been motivated to do this to ensure that only the oxidized portions of the metal layer, and not the bottom portion (Cheng; ¶ [0053]), are removed, and to configure the substrate processing apparatus capable of executing the method. One would have had a reasonable expectation of success because of (1) the similar endeavors of Cheng, Fu, and Yamazaki, comprising similar substrate features, similar metals, and similar metal halide removal gases; and (2) cluster tool substrate processing apparatus with configurable capabilities to adapt to a variety of processing requirements and their configurations are well-known in the art.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Ikeda; Mitsuo et al. (US 2021/0296238; the prior art discloses forming a titanium film in a silicon oxide opening, forming titanium silicide at the bottom of the opening, nitriding the titanium film, and removing by plasma treatment using tungsten chloride a portion of the titanium nitride film formed on sidewalls of the silicon oxide opening);
Tarafdar; Raihan M. et al. (US 2023/0326790; the prior art discloses using a metal halide to remove metal oxide from the bottom of a via or opening.
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/B.A.K./Examiner, Art Unit 2817
/ELISEO RAMOS FELICIANO/Supervisory Patent Examiner, Art Unit 2817
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